I agree with pretty much everything said on this thread so far. Party is experiencing an explosion and so this is a good time to play there. There's lots of new money and that's important because all poker rooms have a life cycle. Between the early explosion and maturity the losing players run out of money one by one and eventually quit. After that, it's only the regulars playing each other with one or two unwary newbies joining from time to time, usually with a Sklansky book under their belts so even if they figure to lose, it's not going to be very much.
With online poker, though, beware of collusion. It does happen and the higher the limit, the more it happens. Some players are good enough to win even if they are being colluded against, so it is not as bad as marked cards or other forms of cheating you may encounter in a real cardroom. But the incidence rate is high, or at least that's the impression one gets if one reads RGP (rec.gambling.poker -- a usenet group reachable via the website
www.recpoker.com and other readers)
And I agree with Hache -- it is a grind and you really have to enjoy it to make it worthwhile otherwise it can drive you nuts. Yes, you can make money if you are bright and disciplined, but the question is whether it is enjoyable enough to be worth it. The answer to that is personal and will vary from person to person. For me the answer is no. It's just too monotonous for my taste. Sports betting on the other hand is another story. Go Braves!!